Limacina helicina seems to fly through the waters off the Svalbard archipelago. This common pelagic snail, a pteropod, performs vital functions in the open ocean ecosystem, grazing on phytoplankton and serving as prey for other drifting organisms and for fish. The biggest threat to its survival isn't predators, however. When the ocean becomes oversaturated with COâ absorbed from the atmosphere, waters become more acidic, and that can interfere with Limacina's ability to build its shell.]]>